This Core resource will provide comprehensive biostatistics consultation and collaboration to all projects in the proposed P01. In addition, it wi II provide support for data storage and computing, and assist with the identification and solution of complex data tasks arising in the course of project activities. Core members will work with project investigators across a wide spectrum of activities, encompassing data acquisition (including study design, feasibility of objectives, and sample size issues), data quality control (preprocessing of data for errors), data analysis (including visualization, biostatistical modeling, and assistance with manuscript writing), and development of innovative customized biostatistics methodologies and tools if required by specific projects. The proposed Biostatistics Core will be housed in the Division of Clinical Trials and Biometry of the Department of Oncology, an active and committed group of biostatistics and bioinformatics faculty members and staff, with access to state-of-the art equipment and a broad range of expertise. This Core resource is the continuation of an existing resource within the original and current P01 program at Johns Hopkins. Core members have a strong commitment to this P01, stemming from a history of collaboration with the investigators of this as well as other related projects. All proposed projects are anticipated to make use of this resource in every aim.